At the beginning of the industrial revolution, Rockefeller, Carnegie and JP Morgan had established monopolistic positions, but in 1913, a tax on the income of the richest was voted in. All hell broke loose in 1929 with the stock market crash. The governement step in. Two opposing blocs emerged : the "liberals" in favour of the New Deal and the "conservatives" who wanted to return to the pre-1929 world. After the Second World War, GDP doubled and the 40 biggest companies accounted for half of production. It was in their interest to accept trade unions and pay taxes in exchange for growth prospects, they became "liberal".